Abstract: The paper aims at the difficulty to obtain a large number of vigorous seedlings of small-grain crops, such as foxtail millet, for genetic material extraction and purity identification by using traditional methods of breeding seedling. According to the rule of crop water requirement, we took loam as the matrix and created a breeding environment with higher moisture content in the low part and lower moisture content in the upper part to make seedlings grow vigorously and healthily. The results showed that: (1) a new technique system was set up for breeding seedlings, including“the choice of matrix, preparation of matrix with higher water content in the lower side, formation of seedling breeding matrix with higher water content in the lower side and lower water content in the upper side, controllable sowing and simple systematic management”; (2) 7 better and 1 optimum matrix ratios, and water content ranges of each part of matrix were screened out; (3) a large quantity of vigorous seedlings were cultivated by controllable sowing and simple systematic management at seedling stage. These methods are used in seedling breeding practice, and have obtained good results, which can provide technical support for the research of small-grain crops.